A cable constituted by a bundle of electric wires each formed of a conductor and an insulating coating layer of polyethylene, polyvinyl chloride, or the like disposed around the conductor, and a sheath layer covering the outer periphery of the bundle has been used as a cable, such as an electric parking brake cable or a wheel speed sensor cable for automobiles. This cable is required to have heat resistance as well as toughness and flexibility because it is exposed to heat released from engines, brake discs, etc.
To meet the required heat resistance, there has been proposed a cable in which an electric wire is covered with a heat-resistant, flame-retardant polyurethane elastomer composition containing a polyurethane elastomer, a halogen flame retardant other than polybromodiphenyl ether, and a carbodiimide compound and in which a sheath layer is formed by irradiating the heat-resistant, flame-retardant polyurethane elastomer composition with an electron beam (see Japanese Unexamined Patent Application Publication No. 6-212073). This cable of related art obtains improved heat resistance through electron beam crosslinking of polyurethane in the sheath layer by electron beam irradiation.